PJM Messages Public Web Service

aid: pjm:pjm-messages-public-api
name: PJM Messages Public Web Service
description: 'The only fully anonymous PJM REST API found on the public surface. It backs the PJM Upcoming
  Changes page and returns the current planned-outage, delayed-data and impact notices for the whole PJM
  eTools estate — affected applications by name and numeric id, the change window as epoch milliseconds,
  required actions, and an access-blocking flag. GET https://messages.pjm.com/messages/rest/public/messages
  returned HTTP 200 with no credential on 2026-07-27, serving application/xml;charset=UTF-8 by default
  and JSON under Accept: application/json. There are no documented query parameters, no paging and no
  filtering — it returns the current notice set as one small document. It is poll-only; PJM registers
  no webhooks, and the alternative subscription channel is email.'
humanURL: https://www.pjm.com/markets-and-operations/etools/upcoming-changes
baseURL: https://messages.pjm.com/messages/rest/public
image: https://www.pjm.com/assets/MVC/responsive/img/pjm-logo.png
tags:
- Status
- Notifications
- Planned Outages
- Grid Operations
- Open Access
properties:
- type: Documentation
  url: https://www.pjm.com/markets-and-operations/etools/upcoming-changes
- type: Guide
  url: https://www.pjm.com/-/media/etools/upcoming-changes-how-to-guide.pdf
- type: JSONSchema
  url: json-schema/pjm-message.json
- type: Examples
  url: examples/_index.yml
- type: AgentSkill
  url: skills/pjm-watch-tool-change-notices.md
- type: StatusPage
  url: https://www.pjm.com/markets-and-operations/etools/upcoming-changes